Studies on the flame photometer for the determination of Na2O and K2O in portland cement

Abstract

A study has been made on the P erkin-Elmer model 52-A flame photometer to establish its suitability for t he determination of Na20 and K 20 in portland cements and cement raw materials, such as argillaceous limestones and clays. An essential factor in the successful appli cation of the method is t he use of suitable standard solutions for each type of material analyzed. Such so lutions were de veloped and excellent res ul ts obtained. This paper gives the photometric res ul ts due to numerous variables and presents a recommended procedure. On cements, t he averages of t he differences betwee n the direct-intensity photometric and the grav imetric values obtained wer e 0.012 p er cent for Na20 and 0.024 percent for K , O. Sligh t ly closer agreement was obtain ed with the internal-standard method, but un certa in t ies due to the possible presence of Li20 give greater re li abili ty to t he direct-in te nsity me thod. The advantages of flam e photometr y , both in time and accuracy, are such as to warrant its recommendation for t he purpose examined.

Improvements in Flame Photometric Determination of Sodium in Portland Cement

“…The other constituents of portland cement are not included in the standards. Eubank and Bogue (7) showed that these standards give reasonably good results, and several years of experience by the cement industry have confirmed this.…”

“…of calcium oxide equivalent to the average amount in Portland cement. It has been shown that no appreciable error is introduced by the normal variation in the amount of calcium in cement (7).…”

“…This suggestion received ready acceptance, and additional development work was carried out by Pritchard, Bogue, and Bean. This resulted, in 1949, in the adoption by the American Society for Testing Materials of a tentative standard method {1) and a study of the subject by Eubank and Bogue (7). The 1952 revision of the federal specification on methods of testing cement included essentially the same procedure {10).…”

Flame Spectrophotometry for Determination of Sodium, Potassium, and Lithium in Glass

“…The application of analysis of variance to an analytical problem has proved very satisfactory in this work, and should be very useful to the analytical chemist in similar problems. THE emission characteristics of the alkali metals in a hot flame (9, IS, 13) and the application of this phenomenon in flame spectrophotometry to the determination of small amounts of these elements (1,2,5,11,15) are well known. However, in the application of this technique for the analysis of any' material in w'hich the three alkalies are present together, a large number of instrumental and interference variables immediately' become apparent.…”